Vulnerability-Lookup

GHSA-PMHV-3RPV-4CGH

Vulnerability from github – Published: 2026-08-28 21:31 – Updated: 2026-08-28 21:31

Details

SpringBlade versions 2.7.3 through 3.5.0 contain a privilege escalation vulnerability that allows authenticated attackers to create system administrator accounts by sending crafted POST requests to an unprotected internal Feign user-creation endpoint exposed via @RestController without authorization checks. Attackers can exploit the gateway's authentication filter, which only validates JWT parsing without verifying user roles or caller identity, and leverage a hardcoded JWT signing key embedded in publicly available JARs to forge tokens and escalate privileges from a low-privilege user to administrator, enabling cross-tenant data pollution and persistent backdoor access.

Severity

8.1 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

8.6 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-56100"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-862"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-28T20:18:30Z",
    "severity": "HIGH"
  },
  "details": "SpringBlade versions 2.7.3 through 3.5.0 contain a privilege escalation vulnerability that allows authenticated attackers to create system administrator accounts by sending crafted POST requests to an unprotected internal Feign user-creation endpoint exposed via @RestController without authorization checks. Attackers can exploit the gateway\u0027s authentication filter, which only validates JWT parsing without verifying user roles or caller identity, and leverage a hardcoded JWT signing key embedded in publicly available JARs to forge tokens and escalate privileges from a low-privilege user to administrator, enabling cross-tenant data pollution and persistent backdoor access.",
  "id": "GHSA-pmhv-3rpv-4cgh",
  "modified": "2026-08-28T21:31:16Z",
  "published": "2026-08-28T21:31:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56100"
    },
    {
      "type": "WEB",
      "url": "https://github.com/chillzhuang/SpringBlade/commit/c69b9547c942c697da2f3ee6a9265b6004abd645"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/sud0why/e73405057dd7414a8c221ef17e0d0059#file-cve-2026-56100-springblade-authbypass-en-md"
    },
    {
      "type": "WEB",
      "url": "https://github.com/chillzhuang/SpringBlade"
    },
    {
      "type": "WEB",
      "url": "https://github.com/chillzhuang/SpringBlade/releases#release-v5.0.0"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/springblade-privilege-escalation-via-exposed-feign-endpoint"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-56100 (GCVE-0-2026-56100)

Vulnerability from cvelistv5 – Published: 2026-08-28 18:00 – Updated: 2026-08-29 11:47 X_Open Source

Title

SpringBlade 2.7.3 < 5.0.0 Privilege Escalation via Exposed Feign Endpoint

Summary

SpringBlade versions from 2.7.3 up to but not including 5.0.0 contain a privilege escalation vulnerability that allows authenticated attackers to create system administrator accounts by sending crafted POST requests to an unprotected internal Feign user-creation endpoint exposed via @RestController without authorization checks. Attackers can exploit the gateway's authentication filter, which only validates JWT parsing without verifying user roles or caller identity, and leverage a hardcoded JWT signing key embedded in publicly available JARs to forge tokens and escalate privileges from a low-privilege user to administrator, enabling cross-tenant data pollution and persistent backdoor access.

Severity

8.6 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

8.1 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-28 20:29 UTC

CWE

CWE-862 - Missing Authorization

Assigner

VulnCheck mitre root

References

5 references

URL	Tags
https://gist.github.com/sud0why/e73405057dd7414a8…	technical-descriptionexploit
https://github.com/chillzhuang/SpringBlade/releas…
https://github.com/chillzhuang/SpringBlade/commit…	patch
https://github.com/chillzhuang/SpringBlade	product
https://www.vulncheck.com/advisories/springblade-…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
SpringBlade	SpringBlade	Affected: 2.7.3 , < 5.0.0 (semver)

Date Public

2026-07-30 00:00

Credits

sud0why

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.